Brief:
FOB can serve as an important indicator for detecting GI bleeding caused by various reasons. In clinical practice, 20% of patients with malignant tumors in the digestive tract can show a positive FOB test in the early stage, while 90% are in the late stage, and this result will continue indefinitely. In addition, GI ulcers, dysentery, rectal polyps, and hemorrhages caused by hemorrhoids can also lead to FOB test positivity.